A number of proliferation-associated nuclear proteins have been described (Wheely and Baserga, 1977, Cell Biol. Int. Rep., vol. 1, p. 13-21; Tan et al., 1987, Nucleic Acids Res., vol. 15, pp. 9299-9308; Gomez-Marquez et al., 1989, J. Biol. Chem., vol. 264 pp. 8451-8454; Feuerstein et al., 1988, J. Cell Biol., vol. 107, pp. 1629-1642; Shawyer et al., 1989, J. Biol. Chem., vol. 264, pp. 1046-1050; Jaskulski et al., 1988, J. Biol. Chem., vol. 263, pp. 10175-10179). Some, such as proliferating cell nuclear antigen (Tan et al., 1987, Nucleic Acids Res., vol. 15, pp. 9299-9308; Jaskulski et al., 1988, J. Biol. Chem., vol. 263, pp. 10175-10179), a co-factor of DNA polymerase delta, participate directly in proliferation. Still others, such as KI-67, are of unknown function (Gerdes et al., 1984, J. Immunol. vol. 133, pp. 1710-1715). In cases involving nuclear phosphoproteins, phosphorylation and dephosphorylation through systems of kinases and phosphatases may be important in coordinating molecular functions (Morla et al., 1989, Cell, vol. 58, pp. 193-203; Chen et al., 1989, Cell, vol. 58, pp. 1193-1198; Cooper and Whyte, 1989, Cell, vol. 58, pp. 1009-1011). While these proteins are expressed under normal physiological conditions, there is the possibility that derangement of the expression of one or more of these proteins could be involved in the growth and development of malignancies.
There is a continuing need in the medical arts for new means to diagnose and prognose cancers. Quick and simple methods can lead to more widespread cancer testing and earlier diagnoses, which can save lives by allowing therapy at earlier stages of the disease process.